Lightweight, Robust, Conductive Composite Fibers Based on MXene@Aramid Nanofibers as Sensors for Smart Fabrics.

Developing one-dimensional fiber-based sensors to meet the requirement of spinnability, portability, flexibility, and easeful conformability in smart wearable devices has attracted increasing interest. Here, we report highly conductive MXene@aramid nanofibers (ANFs) with a distinct skin-core structure by the wet spinning method. MXene, an emerging 2D conductive material, is applied to build internal conductive paths. ANF frameworks function as protective and skeleton structures to reduce the fiber oxidation probability and achieve superior strength. The obtained MXene@ANF fiber with superior conductivity (2515 S m-1) and tensile strength (130 MPa) works as a promising sensor for smart fabrics to detect different human movements with abundant detection motions, fast response time (100 ms), and long service life (up to 1000 cycles). Benefiting from its high flexibility, it can be sewn into textile and gloves as a smart wearable device. Besides superior thermal stability, it shows promising electrothermal properties with wide heating temperature (25-123 °C) and fast heating temperature (10 s). Therefore, the MXene@ANF fiber with the skin-core structure shows great potential as a promising sensor to be applied in electric heating and smart wearable fabrics.